Re: Foreign join pushdown vs EvalPlanQual

On 2015/09/03 14:22, Etsuro Fujita wrote:
> On 2015/09/03 9:41, Robert Haas wrote:
>> That having been said, I don't entirely like Fujita-san's patch
>> either. Much of the new code is called immediately adjacent to an FDW
>> callback which could pretty trivially do the same thing itself, if
>> needed.

> Another idea about that code is to call that code in eg, ExecProcNode,
> instead of calling ExecForeignScan there. I think that that might be
> much cleaner and resolve the naming problem below.

I gave it another thought; the following changes to ExecInitNode would
make the patch much simpler, ie, we would no longer need to call the new
code in ExecInitForeignScan, ExecForeignScan, ExecEndForeignScan, and
ExecReScanForeignScan. I think that would resolve the name problem also.

*** a/src/backend/executor/execProcnode.c
--- b/src/backend/executor/execProcnode.c
***************
*** 247,254 **** ExecInitNode(Plan *node, EState *estate, int eflags)
break;

case T_ForeignScan:
! result = (PlanState *) ExecInitForeignScan((ForeignScan *) node,
! estate, eflags);
break;

case T_CustomScan:
--- 247,269 ----
break;

case T_ForeignScan:
! {
! Index scanrelid = ((ForeignScan *)
node)->scan.scanrelid;
!
! if (estate->es_epqTuple != NULL && scanrelid == 0)
! {
! /*
! * We are in foreign join inside an EvalPlanQual
recheck.
! * Initialize local join execution plan, instead.
! */
! Plan *subplan = ((ForeignScan *)
node)->fs_subplan;
!
! result = ExecInitNode(subplan, estate, eflags);
! }
! else
! result = (PlanState *)
ExecInitForeignScan((ForeignScan *) node,
! estate,
eflags);
! }
break;

Best regards,
Etsuro Fujita